lib/gnutls_int.h

   1 /*
   2  * Copyright (C) 2000-2012 Free Software Foundation, Inc.
   3  *
   4  * Author: Nikos Mavrogiannopoulos
   5  *
   6  * This file is part of GnuTLS.
   7  *
   8  * The GnuTLS is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public License
  10  * as published by the Free Software Foundation; either version 3 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program.  If not, see <http://www.gnu.org/licenses/>
  20  *
  21  */
  22
  23 #ifndef GNUTLS_INT_H
  24 #define GNUTLS_INT_H
  25
  26 #ifdef HAVE_CONFIG_H
  27 #include <config.h>
  28 #endif
  29
  30 #include <stddef.h>
  31 #include <string.h>
  32 #include <stdlib.h>
  33 #include <stdio.h>
  34 #include <ctype.h>
  35 #include <limits.h>
  36 #include <stdint.h>
  37
  38 #ifdef NO_SSIZE_T
  39 #define HAVE_SSIZE_T
  40 typedef int ssize_t;
  41 #endif
  42
  43 #include <sys/types.h>
  44 #include <unistd.h>
  45 #include <sys/stat.h>
  46 #if HAVE_SYS_SOCKET_H
  47 # include <sys/socket.h>
  48 #elif HAVE_WS2TCPIP_H
  49 # include <ws2tcpip.h>
  50 #endif
  51 #include <time.h>
  52 #include <u64.h> /* gnulib for uint64_t */
  53
  54 #ifdef HAVE_LIBNETTLE
  55 # include <nettle/memxor.h>
  56 #else
  57 # include <gl/memxor.h>
  58 # define memxor gl_memxor
  59 #endif
  60
  61 #ifdef __GNUC__
  62 # ifndef _GNUTLS_GCC_VERSION
  63 #  define _GNUTLS_GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__)
  64 # endif
  65 # if _GNUTLS_GCC_VERSION >= 30100
  66 #  define likely(x)      __builtin_expect((x), 1)
  67 #  define unlikely(x)    __builtin_expect((x), 0)
  68 # endif
  69 #endif
  70
  71 #ifndef likely
  72 # define likely
  73 # define unlikely
  74 #endif
  75
  76 /* some systems had problems with long long int, thus,
  77  * it is not used.
  78  */
  79 typedef struct
  80 {
  81   unsigned char i[8];
  82 } uint64;
  83
  84 #include <gnutls/gnutls.h>
  85 #include <gnutls/dtls.h>
  86 #include <gnutls/abstract.h>
  87 #include <system.h>
  88
  89 /*
  90  * They are not needed any more. You can simply enable
  91  * the gnutls_log callback to get error descriptions.
  92
  93 #define BUFFERS_DEBUG
  94 #define WRITE_DEBUG
  95 #define READ_DEBUG
  96 #define HANDSHAKE_DEBUG // Prints some information on handshake
  97 #define COMPRESSION_DEBUG
  98 #define DEBUG
  99 */
 100
 101 /* The size of a handshake message should not
 102  * be larger than this value.
 103  */
 104 #define MAX_HANDSHAKE_PACKET_SIZE 48*1024
 105
 106 #define TLS_MAX_SESSION_ID_SIZE 32
 107
 108 /* The maximum digest size of hash algorithms.
 109  */
 110 #define MAX_HASH_SIZE 64
 111 #define MAX_CIPHER_BLOCK_SIZE 16
 112 #define MAX_CIPHER_KEY_SIZE 32
 113
 114 #define MAX_USERNAME_SIZE 128
 115 #define MAX_SERVER_NAME_SIZE 128
 116
 117 #define SESSION_TICKET_KEY_NAME_SIZE 16
 118 #define SESSION_TICKET_KEY_SIZE 16
 119 #define SESSION_TICKET_IV_SIZE 16
 120 #define SESSION_TICKET_MAC_SECRET_SIZE 32
 121
 122 #define AEAD_EXPLICIT_DATA_SIZE 8
 123 #define AEAD_IMPLICIT_DATA_SIZE 4
 124
 125 #define GNUTLS_MASTER_SIZE 48
 126 #define GNUTLS_RANDOM_SIZE 32
 127
 128 /* DTLS */
 129 #define DTLS_RECORD_WINDOW_SIZE 64
 130
 131 /* TLS Extensions */
 132 /* we can receive up to MAX_EXT_TYPES extensions.
 133  */
 134 #define MAX_EXT_TYPES 32
 135
 136   /**
 137    * gnutls_ext_parse_type_t:
 138    * @GNUTLS_EXT_NONE: Never parsed
 139    * @GNUTLS_EXT_ANY: Any extension type.
 140    * @GNUTLS_EXT_APPLICATION: Application extension.
 141    * @GNUTLS_EXT_TLS: TLS-internal extension.
 142    * @GNUTLS_EXT_MANDATORY: Extension parsed even if resuming (or extensions are disabled).
 143    *
 144    * Enumeration of different TLS extension types.  This flag
 145    * indicates for an extension whether it is useful to application
 146    * level or TLS level only.  This is (only) used to parse the
 147    * application level extensions before the "client_hello" callback
 148    * is called.
 149    */
 150   typedef enum
 151   {
 152     GNUTLS_EXT_ANY = 0,
 153     GNUTLS_EXT_APPLICATION = 1,
 154     GNUTLS_EXT_TLS = 2,
 155     GNUTLS_EXT_MANDATORY = 3,
 156     GNUTLS_EXT_NONE = 4
 157   } gnutls_ext_parse_type_t;
 158
 159
 160 /* expire time for resuming sessions */
 161 #define DEFAULT_EXPIRE_TIME 3600
 162
 163 typedef enum transport_t
 164 {
 165   GNUTLS_STREAM,
 166   GNUTLS_DGRAM
 167 } transport_t;
 168
 169 /* the maximum size of encrypted packets */
 170 #define IS_DTLS(session) (session->internals.transport == GNUTLS_DGRAM)
 171
 172 #define DEFAULT_MAX_RECORD_SIZE 16384
 173 #define TLS_RECORD_HEADER_SIZE 5
 174 #define DTLS_RECORD_HEADER_SIZE (TLS_RECORD_HEADER_SIZE+8)
 175 #define RECORD_HEADER_SIZE(session) (IS_DTLS(session) ? DTLS_RECORD_HEADER_SIZE : TLS_RECORD_HEADER_SIZE)
 176 #define MAX_RECORD_HEADER_SIZE DTLS_RECORD_HEADER_SIZE
 177
 178 #define MAX_RECORD_SEND_SIZE(session) (IS_DTLS(session)?((size_t)gnutls_dtls_get_data_mtu(session)):(size_t)session->security_parameters.max_record_send_size)
 179 #define MAX_RECORD_RECV_SIZE(session) ((size_t)session->security_parameters.max_record_recv_size)
 180 #define MAX_PAD_SIZE 255
 181 #define EXTRA_COMP_SIZE 2048
 182 #define MAX_RECORD_OVERHEAD (MAX_CIPHER_BLOCK_SIZE/*iv*/+MAX_PAD_SIZE+EXTRA_COMP_SIZE+MAX_HASH_SIZE/*MAC*/)
 183 #define MAX_RECV_SIZE(session) (MAX_RECORD_OVERHEAD+MAX_RECORD_RECV_SIZE(session)+RECORD_HEADER_SIZE(session))
 184
 185 #define TLS_HANDSHAKE_HEADER_SIZE 4
 186 #define DTLS_HANDSHAKE_HEADER_SIZE (TLS_HANDSHAKE_HEADER_SIZE+8)
 187 #define HANDSHAKE_HEADER_SIZE(session) (IS_DTLS(session) ? DTLS_HANDSHAKE_HEADER_SIZE : TLS_HANDSHAKE_HEADER_SIZE)
 188 #define MAX_HANDSHAKE_HEADER_SIZE DTLS_HANDSHAKE_HEADER_SIZE
 189
 190 /* This is the maximum handshake message size we send without
 191    fragmentation. This currently ignores record layer overhead. */
 192 #define DTLS_DEFAULT_MTU 1200
 193
 194 /* the maximum size of the DTLS cookie */
 195 #define DTLS_MAX_COOKIE_SIZE 32
 196
 197 /* The maximum number of HELLO_VERIFY_REQUEST messages the client
 198    processes before aborting. */
 199 #define MAX_HANDSHAKE_HELLO_VERIFY_REQUESTS 5
 200
 201 /* defaults for verification functions
 202  */
 203 #define DEFAULT_VERIFY_DEPTH 32
 204 #define DEFAULT_VERIFY_BITS 16*1024
 205
 206 #include <gnutls_mem.h>
 207
 208 #define MEMSUB(x,y) ((ssize_t)((ptrdiff_t)x-(ptrdiff_t)y))
 209
 210 #define DECR_LEN(len, x) do { len-=x; if (len<0) {gnutls_assert(); return GNUTLS_E_UNEXPECTED_PACKET_LENGTH;} } while (0)
 211 #define DECR_LENGTH_RET(len, x, RET) do { len-=x; if (len<0) {gnutls_assert(); return RET;} } while (0)
 212 #define DECR_LENGTH_COM(len, x, COM) do { len-=x; if (len<0) {gnutls_assert(); COM;} } while (0)
 213
 214 #define GNUTLS_POINTER_TO_INT(_) ((int) GNUTLS_POINTER_TO_INT_CAST (_))
 215 #define GNUTLS_INT_TO_POINTER(_) ((void*) GNUTLS_POINTER_TO_INT_CAST (_))
 216
 217 typedef struct
 218 {
 219   uint8_t pint[3];
 220 } uint24;
 221
 222 #include <gnutls_mpi.h>
 223
 224 typedef enum handshake_state_t
 225 { STATE0 = 0, STATE1, STATE2,
 226   STATE3, STATE4, STATE5,
 227   STATE6, STATE7, STATE8, STATE9, STATE11 = 11,
 228   STATE20 = 20, STATE21, STATE22,
 229   STATE30 = 30, STATE31, STATE40 = 40, STATE41, STATE50 = 50,
 230   STATE60 = 60, STATE61, STATE62, STATE70, STATE71
 231 } handshake_state_t;
 232
 233 typedef enum recv_state_t
 234 {
 235   RECV_STATE_0 = 0,
 236   RECV_STATE_DTLS_RETRANSMIT,
 237 } recv_state_t;
 238
 239 #include <gnutls_str.h>
 240
 241 /* This is the maximum number of algorithms (ciphers or macs etc).
 242  * keep it synced with GNUTLS_MAX_ALGORITHM_NUM in gnutls.h
 243  */
 244 #define MAX_ALGOS GNUTLS_MAX_ALGORITHM_NUM
 245
 246 typedef enum extensions_t
 247 {
 248   GNUTLS_EXTENSION_SERVER_NAME = 0,
 249   GNUTLS_EXTENSION_MAX_RECORD_SIZE = 1,
 250   GNUTLS_EXTENSION_CERT_TYPE = 9,
 251   GNUTLS_EXTENSION_SUPPORTED_ECC = 10,
 252   GNUTLS_EXTENSION_SUPPORTED_ECC_PF = 11,
 253   GNUTLS_EXTENSION_SRP = 12,
 254   GNUTLS_EXTENSION_SIGNATURE_ALGORITHMS = 13,
 255   GNUTLS_EXTENSION_SESSION_TICKET = 35,
 256   GNUTLS_EXTENSION_SAFE_RENEGOTIATION = 65281   /* aka: 0xff01 */
 257 } extensions_t;
 258
 259 typedef enum
 260 { CIPHER_STREAM, CIPHER_BLOCK } cipher_type_t;
 261
 262 #define RESUME_TRUE 1
 263 #define RESUME_FALSE 0
 264
 265 /* Record Protocol */
 266 typedef enum content_type_t
 267 {
 268   GNUTLS_CHANGE_CIPHER_SPEC = 20, GNUTLS_ALERT,
 269   GNUTLS_HANDSHAKE, GNUTLS_APPLICATION_DATA,
 270 } content_type_t;
 271
 272
 273 #define GNUTLS_PK_ANY (gnutls_pk_algorithm_t)-1
 274 #define GNUTLS_PK_NONE (gnutls_pk_algorithm_t)-2
 275
 276 /* Message buffers (mbuffers) structures */
 277
 278 /* this is actually the maximum number of distinct handshake
 279  * messages that can arrive in a single flight
 280  */
 281 #define MAX_HANDSHAKE_MSGS 6
 282 typedef struct
 283 {
 284   /* Handshake layer type and sequence of message */
 285   gnutls_handshake_description_t htype;
 286   uint32_t length;
 287
 288   /* valid in DTLS */
 289   uint16_t sequence;
 290
 291   /* indicate whether that message is complete.
 292    * complete means start_offset == 0 and end_offset == length
 293    */
 294   uint32_t start_offset;
 295   uint32_t end_offset;
 296
 297   uint8_t header[MAX_HANDSHAKE_HEADER_SIZE];
 298   int header_size;
 299
 300   gnutls_buffer_st data;
 301 } handshake_buffer_st;
 302
 303 typedef struct mbuffer_st
 304 {
 305   /* when used in mbuffer_head_st */
 306   struct mbuffer_st *next;
 307   struct mbuffer_st *prev;
 308
 309   /* msg->size - mark = number of bytes left to process in this
 310      message. Mark should only be non-zero when this buffer is the
 311      head of the queue. */
 312   size_t mark;
 313
 314
 315   /* the data */
 316   gnutls_datum_t msg;
 317   size_t maximum_size;
 318
 319   /* used during fill in, to separate header from data
 320    * body. */
 321   unsigned int user_mark;
 322
 323   /* Filled in by record layer on recv:
 324    * type, record_sequence
 325    */
 326
 327   /* record layer content type */
 328   content_type_t type;
 329
 330   /* record layer sequence */
 331   uint64 record_sequence;
 332
 333   /* Filled in by handshake layer on send:
 334    * type, epoch, htype, handshake_sequence
 335    */
 336
 337   /* Record layer epoch of message */
 338   uint16_t epoch;
 339
 340   /* Handshake layer type and sequence of message */
 341   gnutls_handshake_description_t htype;
 342   uint16_t handshake_sequence;
 343 } mbuffer_st;
 344
 345 typedef struct mbuffer_head_st
 346 {
 347   mbuffer_st *head;
 348   mbuffer_st *tail;
 349
 350   unsigned int length;
 351   size_t byte_length;
 352 } mbuffer_head_st;
 353
 354 /* Store & Retrieve functions defines:
 355  */
 356
 357 typedef struct auth_cred_st
 358 {
 359   gnutls_credentials_type_t algorithm;
 360
 361   /* the type of credentials depends on algorithm
 362    */
 363   void *credentials;
 364   struct auth_cred_st *next;
 365 } auth_cred_st;
 366
 367 struct gnutls_key_st
 368 {
 369   /* For ECDH KX */
 370   gnutls_pk_params_st ecdh_params;
 371   bigint_t ecdh_x;
 372   bigint_t ecdh_y;
 373
 374   /* For DH KX */
 375   gnutls_datum_t key;
 376   bigint_t KEY;
 377   bigint_t client_Y;
 378   bigint_t client_g;
 379   bigint_t client_p;
 380   bigint_t dh_secret;
 381   /* for SRP */
 382   bigint_t A;
 383   bigint_t B;
 384   bigint_t u;
 385   bigint_t b;
 386   bigint_t a;
 387   bigint_t x;
 388   /* RSA: e, m
 389    */
 390   bigint_t rsa[2];
 391
 392   /* this is used to hold the peers authentication data
 393    */
 394   /* auth_info_t structures SHOULD NOT contain malloced
 395    * elements. Check gnutls_session_pack.c, and gnutls_auth.c.
 396    * Remember that this should be calloced!
 397    */
 398   void *auth_info;
 399   gnutls_credentials_type_t auth_info_type;
 400   int auth_info_size;           /* needed in order to store to db for restoring
 401                                  */
 402   uint8_t crypt_algo;
 403
 404   auth_cred_st *cred;           /* used to specify keys/certificates etc */
 405
 406   int crt_requested;
 407   /* some ciphersuites use this
 408    * to provide client authentication.
 409    * 1 if client auth was requested
 410    * by the peer, 0 otherwise
 411    *** In case of a server this
 412    * holds 1 if we should wait
 413    * for a client certificate verify
 414    */
 415 };
 416 typedef struct gnutls_key_st *gnutls_key_st;
 417
 418
 419 struct record_state_st;
 420 typedef struct record_state_st record_state_st;
 421
 422 struct record_parameters_st;
 423 typedef struct record_parameters_st record_parameters_st;
 424
 425 /* STATE (cont) */
 426
 427 #include <gnutls_hash_int.h>
 428 #include <gnutls_cipher_int.h>
 429 #include <gnutls_compress.h>
 430
 431 typedef struct
 432 {
 433   uint8_t hash_algorithm;
 434   uint8_t sign_algorithm;       /* pk algorithm actually */
 435 } sign_algorithm_st;
 436
 437 /* This structure holds parameters got from TLS extension
 438  * mechanism. (some extensions may hold parameters in auth_info_t
 439  * structures also - see SRP).
 440  */
 441
 442 #define MAX_SIGNATURE_ALGORITHMS 16
 443 #define MAX_SIGN_ALGO_SIZE (2 + MAX_SIGNATURE_ALGORITHMS * 2)
 444
 445 #define MAX_VERIFY_DATA_SIZE 36 /* in SSL 3.0, 12 in TLS 1.0 */
 446
 447 /* auth_info_t structures now MAY contain malloced
 448  * elements.
 449  */
 450
 451 /* This structure and auth_info_t, are stored in the resume database,
 452  * and are restored, in case of resume.
 453  * Holds all the required parameters to resume the current
 454  * session.
 455  */
 456
 457 /* if you add anything in Security_Parameters struct, then
 458  * also modify CPY_COMMON in gnutls_constate.c.
 459  */
 460
 461 /* Note that the security parameters structure is set up after the
 462  * handshake has finished. The only value you may depend on while
 463  * the handshake is in progress is the cipher suite value.
 464  */
 465 typedef struct
 466 {
 467   unsigned int entity; /* GNUTLS_SERVER or GNUTLS_CLIENT */
 468   gnutls_kx_algorithm_t kx_algorithm;
 469
 470   /* The epoch used to read and write */
 471   uint16_t epoch_read;
 472   uint16_t epoch_write;
 473
 474   /* The epoch that the next handshake will initialize. */
 475   uint16_t epoch_next;
 476
 477   /* The epoch at index 0 of record_parameters. */
 478   uint16_t epoch_min;
 479
 480   /* this is the ciphersuite we are going to use
 481    * moved here from internals in order to be restored
 482    * on resume;
 483    */
 484   uint8_t cipher_suite[2];
 485   gnutls_compression_method_t compression_method;
 486   uint8_t master_secret[GNUTLS_MASTER_SIZE];
 487   uint8_t client_random[GNUTLS_RANDOM_SIZE];
 488   uint8_t server_random[GNUTLS_RANDOM_SIZE];
 489   uint8_t session_id[TLS_MAX_SESSION_ID_SIZE];
 490   uint8_t session_id_size;
 491   time_t timestamp;
 492
 493   /* The send size is the one requested by the programmer.
 494    * The recv size is the one negotiated with the peer.
 495    */
 496   uint16_t max_record_send_size;
 497   uint16_t max_record_recv_size;
 498   /* holds the negotiated certificate type */
 499   gnutls_certificate_type_t cert_type;
 500   gnutls_ecc_curve_t ecc_curve; /* holds the first supported ECC curve requested by client */
 501   gnutls_protocol_t version;    /* moved here */
 502
 503   /* FIXME: The following are not saved in the session storage
 504    * for session resumption.
 505    */
 506
 507   /* Used by extensions that enable supplemental data: Which ones
 508    * do that? Do they belong in security parameters?
 509    */
 510   int do_recv_supplemental, do_send_supplemental;
 511 } security_parameters_st;
 512
 513 struct record_state_st
 514 {
 515   gnutls_datum_t mac_secret;
 516   gnutls_datum_t IV;
 517   gnutls_datum_t key;
 518   auth_cipher_hd_st cipher_state;
 519   comp_hd_st compression_state;
 520   uint64 sequence_number;
 521 };
 522
 523 /* These are used to resolve relative epochs. These values are just
 524    outside the 16 bit range to prevent off-by-one errors. An absolute
 525    epoch may be referred to by its numeric id in the range
 526    0x0000-0xffff. */
 527 #define EPOCH_READ_CURRENT  70000
 528 #define EPOCH_WRITE_CURRENT 70001
 529 #define EPOCH_NEXT          70002
 530
 531 struct record_parameters_st
 532 {
 533   uint16_t epoch;
 534   int initialized;
 535
 536   gnutls_cipher_algorithm_t cipher_algorithm;
 537   gnutls_mac_algorithm_t mac_algorithm;
 538   gnutls_compression_method_t compression_algorithm;
 539
 540   /* for DTLS */
 541   uint64_t record_sw[DTLS_RECORD_WINDOW_SIZE];
 542   unsigned int record_sw_size;
 543
 544   record_state_st read;
 545   record_state_st write;
 546
 547   /* Whether this state is in use, i.e., if there is
 548      a pending handshake message waiting to be encrypted
 549      under this epoch's parameters.
 550    */
 551   int usage_cnt;
 552 };
 553
 554 typedef struct
 555 {
 556   unsigned int priority[MAX_ALGOS];
 557   unsigned int algorithms;
 558 } priority_st;
 559
 560 typedef enum
 561 {
 562   SR_DISABLED,
 563   SR_UNSAFE,
 564   SR_PARTIAL,
 565   SR_SAFE
 566 } safe_renegotiation_t;
 567
 568 /* For the external api */
 569 struct gnutls_priority_st
 570 {
 571   priority_st cipher;
 572   priority_st mac;
 573   priority_st kx;
 574   priority_st compression;
 575   priority_st protocol;
 576   priority_st cert_type;
 577   priority_st sign_algo;
 578   priority_st supported_ecc;
 579
 580   /* to disable record padding */
 581   unsigned int no_extensions:1;
 582   unsigned int no_padding:1;
 583   unsigned int allow_large_records:1;
 584   safe_renegotiation_t sr;
 585   unsigned int ssl3_record_version:1;
 586   unsigned int server_precedence:1;
 587   unsigned int allow_key_usage_violation:1;
 588   /* Whether stateless compression will be used */
 589   unsigned int stateless_compression:1;
 590   unsigned int additional_verify_flags;
 591 };
 592
 593
 594 /* DH and RSA parameters types.
 595  */
 596 typedef struct gnutls_dh_params_int
 597 {
 598   /* [0] is the prime, [1] is the generator.
 599    */
 600   bigint_t params[2];
 601   int q_bits; /* length of q in bits. If zero then length is unknown.
 602               */
 603 } dh_params_st;
 604
 605 typedef struct
 606 {
 607   gnutls_dh_params_t dh_params;
 608   int free_dh_params;
 609   gnutls_rsa_params_t rsa_params;
 610   int free_rsa_params;
 611 } internal_params_st;
 612
 613 /* DTLS session state
 614  */
 615 typedef struct
 616 {
 617   /* HelloVerifyRequest DOS prevention cookie */
 618   uint8_t  cookie[DTLS_MAX_COOKIE_SIZE];
 619   uint8_t cookie_len;
 620
 621   /* For DTLS handshake fragmentation and reassembly. */
 622   uint16_t hsk_write_seq;
 623   /* the sequence number of the expected packet */
 624   unsigned int hsk_read_seq;
 625   uint16_t mtu;
 626
 627   /* a flight transmission is in process */
 628   unsigned int flight_init:1;
 629   /* whether this is the last flight in the protocol  */
 630   unsigned int last_flight:1;
 631
 632   /* the retransmission timeout in milliseconds */
 633   unsigned int retrans_timeout_ms;
 634   /* the connection timeout in milliseconds */
 635   unsigned int total_timeout_ms;
 636
 637   unsigned int hsk_hello_verify_requests;
 638
 639   /* non blocking stuff variables */
 640   unsigned int blocking:1;
 641   /* starting time of current handshake */
 642   struct timespec handshake_start_time;
 643
 644   /* The actual retrans_timeout for the next message (e.g. doubled or so)
 645    */
 646   unsigned int actual_retrans_timeout_ms;
 647
 648   /* timers to handle async handshake after gnutls_handshake()
 649    * has terminated. Required to handle retransmissions.
 650    */
 651   time_t async_term;
 652
 653   /* last retransmission triggered by record layer */
 654   struct timespec last_retransmit;
 655   unsigned int packets_dropped;
 656 } dtls_st;
 657
 658
 659 typedef union
 660 {
 661   void *ptr;
 662   uint32_t num;
 663 } extension_priv_data_t;
 664
 665 typedef struct
 666 {
 667   /* holds all the parsed data received by the record layer */
 668   mbuffer_head_st record_buffer;
 669
 670   int handshake_hash_buffer_prev_len;           /* keeps the length of handshake_hash_buffer, excluding
 671                                                  * the last received message */
 672   gnutls_buffer_st handshake_hash_buffer;       /* used to keep the last received handshake
 673                                                  * message */
 674   unsigned int resumable:1;              /* TRUE or FALSE - if we can resume that session */
 675   unsigned int ticket_sent:1;            /* whether a session ticket was sent */
 676   handshake_state_t handshake_state;    /* holds
 677                                          * a number which indicates where
 678                                          * the handshake procedure has been
 679                                          * interrupted. If it is 0 then
 680                                          * no interruption has happened.
 681                                          */
 682
 683   int invalid_connection:1;     /* true or FALSE - if this session is valid */
 684
 685   int may_not_read:1;           /* if it's 0 then we can read/write, otherwise it's forbiden to read/write
 686                                  */
 687   int may_not_write:1;
 688   int read_eof:1;               /* non-zero if we have received a closure alert. */
 689
 690   int last_alert;               /* last alert received */
 691
 692   /* The last handshake messages sent or received.
 693    */
 694   int last_handshake_in;
 695   int last_handshake_out;
 696
 697   /* priorities */
 698   struct gnutls_priority_st priorities;
 699
 700   /* resumed session */
 701   unsigned int resumed:1;  /* RESUME_TRUE or FALSE - if we are resuming a session */
 702   unsigned int resumption_requested:1; /* non-zero if resumption was requested by client */
 703   security_parameters_st resumed_security_parameters;
 704
 705   /* These buffers are used in the handshake
 706    * protocol only. freed using _gnutls_handshake_io_buffer_clear();
 707    */
 708   mbuffer_head_st handshake_send_buffer;
 709   handshake_buffer_st handshake_recv_buffer[MAX_HANDSHAKE_MSGS];
 710   int handshake_recv_buffer_size;
 711
 712   /* this buffer holds a record packet -mostly used for
 713    * non blocking IO.
 714    */
 715   mbuffer_head_st record_recv_buffer;   /* buffer holding the unparsed record that is currently
 716                                          * being received */
 717   mbuffer_head_st record_send_buffer;   /* holds cached data
 718                                          * for the gnutls_io_write_buffered()
 719                                          * function.
 720                                          */
 721   size_t record_send_buffer_user_size;  /* holds the
 722                                          * size of the user specified data to
 723                                          * send.
 724                                          */
 725
 726   int expire_time;              /* after expire_time seconds this session will expire */
 727   struct mod_auth_st_int *auth_struct;  /* used in handshake packets and KX algorithms */
 728
 729   /* this is the highest version available
 730    * to the peer. (advertized version).
 731    * This is obtained by the Handshake Client Hello
 732    * message. (some implementations read the Record version)
 733    */
 734   uint8_t adv_version_major;
 735   uint8_t adv_version_minor;
 736
 737   /* if this is non zero a certificate request message
 738    * will be sent to the client. - only if the ciphersuite
 739    * supports it.
 740    */
 741   int send_cert_req;
 742
 743   /* bits to use for DHE and DHA
 744    * use _gnutls_dh_get_prime_bits() and gnutls_dh_set_prime_bits()
 745    * to access it.
 746    */
 747   uint16_t dh_prime_bits;
 748
 749   size_t max_handshake_data_buffer_size;
 750
 751   /* PUSH & PULL functions.
 752    */
 753   gnutls_pull_timeout_func pull_timeout_func;
 754   gnutls_pull_func pull_func;
 755   gnutls_push_func push_func;
 756   gnutls_vec_push_func vec_push_func;
 757   gnutls_errno_func errno_func;
 758   /* Holds the first argument of PUSH and PULL
 759    * functions;
 760    */
 761   gnutls_transport_ptr_t transport_recv_ptr;
 762   gnutls_transport_ptr_t transport_send_ptr;
 763
 764   /* STORE & RETRIEVE functions. Only used if other
 765    * backend than gdbm is used.
 766    */
 767   gnutls_db_store_func db_store_func;
 768   gnutls_db_retr_func db_retrieve_func;
 769   gnutls_db_remove_func db_remove_func;
 770   void *db_ptr;
 771
 772   /* post client hello callback (server side only)
 773    */
 774   gnutls_handshake_post_client_hello_func user_hello_func;
 775
 776   /* holds the selected certificate and key.
 777    * use _gnutls_selected_certs_deinit() and _gnutls_selected_certs_set()
 778    * to change them.
 779    */
 780   gnutls_pcert_st *selected_cert_list;
 781   int selected_cert_list_length;
 782   struct gnutls_privkey_st *selected_key;
 783   int selected_need_free:1;
 784
 785   /* holds the extensions we sent to the peer
 786    * (in case of a client)
 787    */
 788   uint16_t extensions_sent[MAX_EXT_TYPES];
 789   uint16_t extensions_sent_size;
 790
 791   /* is 0 if we are to send the whole PGP key, or non zero
 792    * if the fingerprint is to be sent.
 793    */
 794   int pgp_fingerprint;
 795
 796   /* This holds the default version that our first
 797    * record packet will have. */
 798   uint8_t default_record_version[2];
 799
 800   void *user_ptr;
 801
 802   int enable_private;           /* non zero to
 803                                  * enable cipher suites
 804                                  * which have 0xFF status.
 805                                  */
 806
 807   /* Holds 0 if the last called function was interrupted while
 808    * receiving, and non zero otherwise.
 809    */
 810   int direction;
 811
 812   /* This callback will be used (if set) to receive an
 813    * openpgp key. (if the peer sends a fingerprint)
 814    */
 815   gnutls_openpgp_recv_key_func openpgp_recv_key_func;
 816
 817   /* If non zero the server will not advertise the CA's he
 818    * trusts (do not send an RDN sequence).
 819    */
 820   int ignore_rdn_sequence;
 821
 822   /* This is used to set an arbitary version in the RSA
 823    * PMS secret. Can be used by clients to test whether the
 824    * server checks that version. (** only used in gnutls-cli-debug)
 825    */
 826   uint8_t rsa_pms_version[2];
 827
 828   /* Here we cache the DH or RSA parameters got from the
 829    * credentials structure, or from a callback. That is to
 830    * minimize external calls.
 831    */
 832   internal_params_st params;
 833
 834   /* To avoid using global variables, and especially on Windows where
 835    * the application may use a different errno variable than GnuTLS,
 836    * it is possible to use gnutls_transport_set_errno to set a
 837    * session-specific errno variable in the user-replaceable push/pull
 838    * functions.  This value is used by the send/recv functions.  (The
 839    * strange name of this variable is because 'errno' is typically
 840    * #define'd.)
 841    */
 842   int errnum;
 843
 844   /* Function used to perform public-key signing operation during
 845      handshake.  Used by gnutls_sig.c:_gnutls_tls_sign(), see also
 846      gnutls_sign_callback_set(). */
 847   gnutls_sign_func sign_func;
 848   void *sign_func_userdata;
 849
 850   /* minimum bits to allow for SRP
 851    * use gnutls_srp_set_prime_bits() to adjust it.
 852    */
 853   uint16_t srp_prime_bits;
 854
 855   /* A handshake process has been completed */
 856   unsigned int initial_negotiation_completed:1;
 857
 858   struct
 859   {
 860     uint16_t type;
 861     extension_priv_data_t priv;
 862     int set:1;
 863   } extension_int_data[MAX_EXT_TYPES];
 864
 865   struct
 866   {
 867     uint16_t type;
 868     extension_priv_data_t priv;
 869     int set:1;
 870   } resumed_extension_int_data[MAX_EXT_TYPES];
 871   /* The type of transport protocol; stream or datagram */
 872   transport_t transport;
 873
 874   /* DTLS session state */
 875   dtls_st dtls;
 876
 877   /* if set it means that the master key was set using
 878    * gnutls_session_set_master() rather than being negotiated. */
 879   unsigned int premaster_set:1;
 880
 881   unsigned int cb_tls_unique_len;
 882   unsigned char cb_tls_unique[MAX_VERIFY_DATA_SIZE];
 883
 884   recv_state_t recv_state; /* state of the receive function */
 885
 886   /* If you add anything here, check _gnutls_handshake_internal_state_clear().
 887    */
 888 } internals_st;
 889
 890 /* Maximum number of epochs we keep around. */
 891 #define MAX_EPOCH_INDEX 16
 892
 893 struct gnutls_session_int
 894 {
 895   security_parameters_st security_parameters;
 896   record_parameters_st *record_parameters[MAX_EPOCH_INDEX];
 897   internals_st internals;
 898   gnutls_key_st key;
 899 };
 900
 901
 902 /* functions
 903  */
 904 void _gnutls_free_auth_info (gnutls_session_t session);
 905
 906 /* These two macros return the advertised TLS version of
 907  * the peer.
 908  */
 909 #define _gnutls_get_adv_version_major( session) \
 910         session->internals.adv_version_major
 911
 912 #define _gnutls_get_adv_version_minor( session) \
 913         session->internals.adv_version_minor
 914
 915 #define set_adv_version( session, major, minor) \
 916         session->internals.adv_version_major = major; \
 917         session->internals.adv_version_minor = minor
 918
 919 void _gnutls_set_adv_version (gnutls_session_t, gnutls_protocol_t);
 920 gnutls_protocol_t _gnutls_get_adv_version (gnutls_session_t);
 921
 922 int _gnutls_is_secure_mem_null (const void *);
 923
 924 inline static gnutls_protocol_t
 925 _gnutls_protocol_get_version (gnutls_session_t session)
 926 {
 927   return session->security_parameters.version;
 928 }
 929
 930 #define gnutls_protocol_get_version _gnutls_protocol_get_version
 931
 932 inline static void
 933 _gnutls_set_current_version (gnutls_session_t session,
 934                              gnutls_protocol_t version)
 935 {
 936   session->security_parameters.version = version;
 937 }
 938
 939 #endif /* GNUTLS_INT_H */